1. Field of the Invention
The present invention generally relates to transmission of video frames and more particularly to direct broadcasting of the video frames in an interactive TV network.
2. Description of the Related Arts
Interactive television (TV) systems are known from for example U.S. Pat. No. 5,233, 654 (the '654 patent). The system described in the '654 patent includes a receiver having a computer with sufficient storage to store interactive programs. In order to make interactive TV less costly and therefore more attractive to consumer acceptance, it is desirable to keep storage requirements in the receiver to a minimum. This is achieved by regularly transmitting executable code for the desired applications rather than requiring that the applications be continuously stored in the receiver.
Audio and visual data are regularly broadcasted to provide data for associated applications stored in the receiver. Catalog applications are a particular type of interactive TV applications that can be downloaded and stored in the receiver. The catalog applications include a plurality of video frames as their associated data. The plurality of video frames represent a catalog for users to select particular items of interest. The catalog applications and the associated data are broadcasted at regular intervals. Once a catalog application is downloaded to the receiver, users download the plurality of video frames and browse through the video frames as they navigate through the catalog of the catalog application in search of the items of interest. Browsing through the plurality of video frames can be time consuming when there is substantial latency delay associated with downloading the plurality of video frames.
Particularly, at any one time there may be a multitude of interactive TV applications and their associated data being simultaneously transmitted to a multitude of users. The amount of bandwidth reserved for broadcasts of a particular interactive TV application and its associated data may become limited. Consequently, as increased numbers of users subscribe to the interactive TV system, the frequency of regular rebroadcasts of data for an associated catalog application is reduced. Users executing the catalog application experience increased latency delay as they browse through the plurality of video frames of the catalog application. Reducing latency delay in the operation of interactive TV applications is an important feature in the operation of the interactive TV system.
Therefore, it is desirable to provide catalog applications and their associated data, and a method of operating the same which reduce latency delay associated with downloading the catalog applications.